score = int(input("请输入分数："))

if score >100 or score <0:
    print("输入的分数有误")
    score = int(input("请重新输入分数："))
else:
    if score >= 90:
        print("优秀")
    elif score >= 80:
        print("良好")
    elif score >= 60:
        print("及格")
    else:
        print("不及格")
